Fertilizing pomegranates is pretty easy for home gardeners. Follow the tips below and you should have good success and lots of fruit to enjoy!
Growing Conditions
The pomegranate is a tropic or subtropic plant. That means it does well in dry, hot conditions and prefers full sun. Some varieties can take cold down to 18 degrees, while a few can withstand temperatures as low as 10 degrees. Some varieties produce edible fruit, while others are more ornamental, producing only a few small fruits. The plant can tolerate most any soil type as long as it has good drainage.
Soil pH is important...
For best pomegranate performance, soils should have a pH ranging from 6.0 to 7.0.
Soil pH is a measurement of the alkalinity or acidity of soil and is measured on a scale of 1-14, with 7 as the neutral mark. Any measurement below 7 is considered acid and anything above 7 is considered alkaline. Acid soils are often referred to as "sour" and alkaline soils as "sweet." A pH of 5.5 is 10 times more acidic than a pH of 6.5. Conversely, a pH of 8.5 is 10 times more alkaline than a pH of 7.5.
You can test your own soil by purchasing a soil pH test kit from your local nursery and garden center or you can buy a soil test kit online here. Your local Extension office may also provide soil testing services. Most soil testing kits provide instructions for adjusting soil pH, or you can get this information from your local nursery and garden center professional or extension service agent. Basically speaking, to raise the pH number you will need to apply limestone. To lower the number (make more acid) you'll need to apply chelated iron, soil sulfur, or aluminum sulfate.
Nutrient and fertilizer needs...
First, water is the most critical nutrient for establishment of young pomegranate trees, particularly during the first year after planting. For established trees, adequate irrigation, especially during dry periods, is very important to improve growth, fruit set, yield, and fruit size. Fruit will drop prematurely and will split if trees are not getting enough water during dry spells.
Unless you have a very sandy soil, pomegranates need very little fertilizer. The only element they really need is nitrogen, and how much is applied will depend on the age of the plant. Don't fertilize pomgranates at all during their first year of life. Apply about 2 ounces of nitrogen per plant during the second year in spring. Each year therafter you can add another ounce. By the 5th year 6 to 8 ounces of nitrogen per tree. A mature tree of 15 years needs about 12 ounces (3/4 pound) of nitrogen per year. These figures are actual nitrogen. No bag of nitrogen fertilizer is 100% nitrogen. So you'll have to do a little math. If your nitrogen fertilizer is 34% (Ammonium Nitrate 34-0-0) your fertilizer contains 34 pounds of nitrogen per 100 pound bag, 17 pounds per 50 pound bag, 8.5 pounds per 25 pounds, 4.25 pounds per 12 pounds, 2 pounds per 6 pounds and so on. Fertilizer should be applied in late winter, before new leaves begin to emerge in spring.
Keep in mind that too much fertilizer is bad, so it's better to aplly less than more. Too much fertilizer will cause heavier foliage growth, which can effect fruit production and even cause the fruit to drop prematurely. Applying too much fertilizer or applying it later in the year than recommended can cause fruit to mature late, and have poor color and poor taste quality.
Alternatively, you can do as I do regarding feeding pomegranates. I'm one of those organic "nuts" that would rather use natural methods of fertilization when feeding plants that bear fruit which will end up on my kitchen table. Instead of using commercial fertilizers I simply use mulch and compost. Mulching plants with composted manures and other organic composts can supply the nitrogen that pomegranates need while eliminating the possibility of burning plants.
Other Tips
- If your pomegranate tree is growing poorly this may or may not mean that it needs fertilizer. If there isn't a nutrient deficiency and you apply fertilizer it can make problems worse. If the pomegranate tree is not growing well or appears unhealthy, a soil test should be done to determine if nutrient deficiencies are causing the problem.
- Mulch with rotted manure and other compost to fill the soil with nitrogen as needed for the tree.
